A Simplified Anchorage Assessment Jig
Ashish Kushwah, Saurabh
Department of Orthodontics & Dentofacial Orthpaedics, Pacific Dental College & Research Centre, Udaipur,
A Simplified Anchorage
Department of Orthodontics & Dentofacial Orthpaedics, Institute of dental education & advanced studies,
Gwalior, Madhya Pradesh.
J Contemp Orthod 2020;4(4):
Department of Orthodontics & Dentofacial Orthpaedics, Eklavya Dental College, Kothputli, Rajasthan.
Anchorage in orthodontics is one of the most important consideration during extraction
treatment planning. Unwanted movement of molars in extraction space is called anchorage loss.
Anchorage loss can be assessed by Cephalometrics but superimposition is one of the main dis-
Source of Support:
Conflict of Interest:
advantages of this method. Thus, in this article we used a modified “Nance palatal arch" which
helps to assess anchorage loss during different stages of treatment.
Anchorage, Anchorage loss, Nance palatal arch, Superimposition.
Separating media (Cold mould seal).
Cold cure acrylic resin.
Anchorage planning in orthodontics has his own importance.
Pre-treatment/ Pre- retraction plaster model.
Anchorage is the most important factor for deciding treatment
outcomes. Usually crowding and bimaxillary protrusion cases
DESIGN AND FABRICATION
require anchorage auxiliaries to enhance the anchorage
value. In spite of all these preparations sometime unwanted
The design of the “Anchorage Assessment Jig” is a
tooth movement of posteriors occur in the extraction space.
modification of “Nance palatal arch”.
Anchorage loss is the reciprocal movement of posterior teeth
Take one 10 cm length 20 gauge stainless steel wire.
occuring during retraction of anterior segment for correction of
Adopt it in pre-treatment/ pre- retraction maxillary
anteroposterior discrepancy. For assessment of anchorage loss
model at palatal rugae area in a fashion that both end
a anatomical landmark is required which is stable in overall
of the wire should be towards maxillary first molar.
According to Bailey et al palatal rugae
Make a 90
bend upward & outward at the junction of
area was a stable landmark in extraction and non extraction
proximal contact area of second premolar and first
cases to assess anchorage loss. Anchorage loss can be easily
assessed on cephalograms or CBCT record but this method
After 5 mm of 90 bend make another bend towards
was quite expensive and required radiographic exposure.
central fossa of maxillary first molar and cut the
In this article we discussed a simplified anchorage assessment
Apply separating media (cold mould seal) on palatal
jig which is a modified “Nance palatal arch”.
This helps the
rugae area and make a palatal button at the rugae area
clinician to assess anchorage loss on plaster model at any
over the wire.
stage of the treatment and on the basis of the jig measurement
By placing this jig at any stage of retraction a clinician
clinician can modify their treatment plan.
can assess anchorage loss. (Figure A, B, & C)
20 gauge stainless steel round wire.
Hard wire cutter.
Journal of Contemporary Orthodontics, Oct-Dec 2020; 4(4):41-43
Ashish Kushwah et al
Anchorage consideration is nonnegotiable part of the orthodontic
treatment. Anchorage loss is a multifactorial response aided
by extent of extraction site, anchorage unit, age, bone density,
thickness of cancellous bone, root position, appliance design and
amount of crowding & overjet.
For assessment of anchorage loss stable landmarks was required.
According to Hoggan et al third palatal rugae area was the stable
area in maxilla for anchorage assessment.
Almeida reported in
his study that lingual foramen or mental foramen was a stable
Figure A. Jig placement before retraction
Three dimensional scanning and superimposition methods were
advocated of assessing the anchorage loss because of its
accuracy and reliability. Various studies
found that these
superimposition techniques are regarded as accurate and reliable
in the comparison of plaster models. Radiographic exposure and
cost makes dental study model as more acceptable for clinician
to assess anchorage loss in clinical practice.
This simplified anchorage assessment jig having properties like
easy fabrication steps, economic armamentarium, no
radiographic exposure and a single jig for overall treatment of a
patient makes it more useful in comparison to other methods.
Figure B. Jig placement at mid of retraction
This “Anchorage Assessment Jig” helps the clinician to assess
accurate anchorage loss at any stage of orthodontic treatment and
linician can change his anchorage auxiliaries or can easily
enhance the anchorage preparation on the basis of “Anchorage
Assessment Jig” value. This jig provides a real time value of
anchorage loss. Easy in office fabrication and simple application
of this jig makes it more effective. Clinician can also assess the
amount of anchorage loss during levelling and alignment. This
economic jig helps to clinician to change their anchorage plan
according to their need.
Figure C. Jig placement at occlusal surface of Molar at mid of
FINANCIAL SUPPORT AND SPONSORSHIP
CONFLICT OF INTEREST
Anchorage loss can be assessing at any stage
There are no conflicts of interest.
Easy to fabricate.
No specific lab work require to fabrication of this jig.
Proffit WR, Field HW, Sarver DM. Contemporary
Anchorage preparation can be changed at any stage
Orthodontics 5th edition, C.V. Mosby Co; 2013.p. 180-181.
Geron S, Shpack N, Kandos S, Davidovitch M, Vardimon
No radiographic exposure.
AD. Anchorage Loss—A Multifactorial Response.
Bailey LT, Esmailnejad A, Almeida MA. Stability of the
palatal rugae as landmarks for analysis of dental casts in
extraction and nonextraction cases. Angle Orthod
Hoggan BR, Sadowsky C. The use of palatal rugae for the
assessment of anteroposterior tooth movements. Am J
Orthod Dentofacial Orthop 2001;119:482-8.
Nance HN. The limitation of orthodontic treatment. Am J
Orthod Oral Surg 1947; 33: 253-301.
Hart A, Taft L, Greenberg SN. The effectiveness of
differential moments in establishing and maintaining
Am J Orthod Dentofacial Orthop.
Almeida MA, Philips C, Kula K, Tulloch C. Stability of
the palatal rugae as landmarks for analysis of dental casts.
Sousa MV, Vasconcelos EC, Janson G, Garib D, Pinzan
A. Accuracy and reproducibility of 3-dimensional digital
model measurements. Am J Orthod Dentofacial Orthop
Fleming PS, Marinho V, Johal A. Orthodontic
measurements on digital study models compared with
plaster models: a systematic review. Orthod Craniofac Res
Journal of Contemporary Orthodontics, Oct-Dec 2020;4(4):41-43